Electrical signaling system.



F, M. SLOUGH.

ELECTRICAL SIGNALING SYSTEM.

APPLICATION FILED JULY 10, 1906.

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GAL SIGNALING SYSTEM.

APPLICATION EILED JULY 10, 1906.

Patented Aug. 31

2 SHEETS-SHEET 2.

flllalilmw tlNITEE STATES PATENT FRANK Id. SLOUGH, 0E3 ELYRIA, (EH10, ASSIGNGLZ 3 THE DEAN ELEGTRIC COMPANY, OF ELYEUL,

OHKQ, A CGRPQBATION 0F (BRIO.

ELECTRICAL SIG-NALIIJG SYSTEM.

To all whom it may concern:

Be it known that I, FRANK M. SLo oon', a citizen of the United States, residing at Elyria, in the county of Lorain and State of Ohio, have invented certain new and useful improvements in Electrical Signaling Systems, of which thefollowing is a specification, reference being had therein to the accompanying drawing.

T his inventionrelates to electrical signaling systems and especially to what are called harmpnic signaling systems.

It is particularly applicable to signaling over telephone lines for the purpose of selecting one party alone out of several on the same line.

-The object of the invention is to perfect and simplify apparatus of this class, reducing the amount of apparatus required by employing pole changers instead of generators and using a minimum number of con tacts thereon.

Further objects will appear hereinafter.

Heretofore it has been found diflicult to construct reeds or armatures for harmonic Vibrators or pole changers which would vibrate at a constant periodicity, especially after they have operated for a considerable length of time. It is exceedingly desirable, therefore, to eliminate all chance for mechanical change in the reed and to this end the spring and armature are all made in one piece according to the present invention. ld oreover, with reeds vibrating at a low rate of speed there is, of course, very little trouble experienced in maintaining a constant rate. These operating reeds are driven by motor magnets deriving their current from contact devices controlled by the slow reed, and they can be readily synchronized, or more accurately tuned, by means of an extra winding placed on each motor magnet and controlled in the vibration of its own reed. Ordinarily I prefer to use the slowest of a set of vibrating reeds as the master or controlling reed, so, that While each of the set governs its own synchronizing Winding, there is always a controlling grasp extended by the master reed and acting at intervals on each of the other reeds to prevent departure by either acceleration or retardation from ihtfj desired rate.

Instead of employing one of a set of Working reeds for a master reed, I may provide Specification of Letters Patent. Application rota =l'uly 1G,

a separate and distinct mechanism for this purpose ed magnet and reed, whose design is such that a very constant rate of vibration will be maintained.

In the ordinary four-frequency harmonic signaling system, as employed by the Dean Electric Company, the frequencies employed are-l6, 33, 50 and (56, respectively; Of these I sel ct the Bicycle vibrator, being the slowest, as the standard or master vibrator. Each of theother vibrators has two windings, one in series with a contact controlled in its own movement and the other depending upon the master vibrator. The connections are such that these second windings on the three higher vibrators receive impulses or currents from the vibration of the ltl-cycle vibrator. In other-words, the cycle vibrator will receive an extra impulse every two vibrations, the 50-cycle vibrator every three vibrations, and the (SS-cycle vi.- brator every four vibrations. If one of these armatures had a tendency to speed up, these extra pulsations would retard its movement and bring it back to itsnormal period. Conversely, if an armature had a tendency to retardation, these extra pulsations would tend to accelerate it and bring it up to normal speed. The synchronizing windings, as they may be called, on the three vibrators are placed in multiple b' preference, but

when properly constructed, they can of course be operated in series.

The invention is illustrated in the accompanying drawings in ivhich- Figure 1 is a diagram of a. harmonic v1- brator setv consisting of four units, arranged so as to make 16, 33, 50 and (36 cycles of movement per second rcspecti\"cly, the low speed vibrator on the left furnishing synchronizing impulses in the other three. Fig. 2 is a similar diagram showing four vi brators, with a. separate master vibrator supplying the synchronizing impulses.

ieferring to these fig'ires, I may state at the outset that the apparatus and circuits illustrated are designed especially for use in telephone systems.

In Fig. 1 P represents the calling plug of an o erators air which is adapted to cooperate with the jack Jof a ti ephone line l-2 serving four stations A, 9. r, and The tip and sleeve conductors b t of the Patented 31.. 1.909. was. seria naseaeaa.

I cord lead from the tip and sleeve of the plug J other side.

respectively, to the ringing key K, which is normally closed so as to complete the talking circuit through the conductors 5 and 6 to the other-plug of the pair, which is not illustrated. This portion of the diagramis not complete as to a telephone system, but is meant to suggest all the necessary apparatus and circuits required to constitutean opera-j tively, each terminating at the secondary ofthe transformer which is grounded on the These transformers are associated with the four pole changers V, V, V and V Each of these has a vibrating member '0, controlled by a motor magnet M with two windings, except the first magnet which only has one winding, The primary winding of each transformer is connected on one side tothe contacts-1314, and on the other side to the contacts 15 16. Between the contacts l3 and 15 a spring arm 17 vibrates and betweenthe contacts 14: and 16 a similar arm 18 vibrates. Both of these arms are carried on the vibrator n, which also carries a stub spring 19 which makes and breaks with the contact 20 of the motor magnet circuit. The spring 17 is insulated from the vibrator, but the other two springs, 18 and 19, are in metallic contact therewith, and are thereby connected to ground.

From the main battery B a feed wire 21 extends to all the pole changers, with individual branches 22, 23, 24 and 25 extending to-the several motor magnets. In the pole changer V the wire 22 passes to the magnet M, supplying current to both windings, which are connected on the other side through the wire 26 to the contact 20. This pole' changer V has a normal periodicity of 16, and as I. have stated, this slow speed renders it comparatively easy to maintain a constant rateof vibration. The other three pole changers, however, require synchronizing, and the slow speed apparatus V is employed for this purpose in the following manner: taking the pole changer V for eX- ample, the magnet M has two windings, viz., a motor winding m and a synchronizing winding m. The circuit of the motor winding is through wire 23 to the magnet and then by wire 27 to the contact 28 cooperating with'the stub spring 29 on the vibrator 0 and thence toground. The circuit of the synchronizing winding, however, is traced through the feed wire 23 to'the magnet and then by branch 30 to the main synchronizing wire 31 and so to the contact 20 and spring 19 of the master vibrator V, which supplies the ground to complete the circuit through its vibrating arm 21. The arrangement of the other pole changers V and V is the same as that of V, hence they will need no separate description and I may pass at once to the statement of operation.

Assuming the circuit of the main battery B to be closed, from the bus 6 on to the feed wire 21, the vibrators vof the pole changers will all start up and oscillate continuously. In oscillating, they move the springs 17 and 18 back and forth between the respective pairs of primary contacts, thereby producing J0 and 70 are manipulate As before stated, the vibration of the arm "a in the pole changer V is taken as the standard, this arm being adjusted for constant vibration. lts motor magnet works directly on the following simple circuit: B, 21, 22, M, 26, 20. 19, 'v, and ground. As the con- .tacts 19 and 20 make and break the magnet oscillates the arm back and forth. Each of the other pole changers works on an individual motor circuit similar to the following: B, 21, 23, m, 27, 28, r and ground. Each of the others also has a synchronizing circuit similar to the following: B, 21, 23, m, 30, 31, 20, 19, v and ground. Obviously, a pulsation of current will be sent over this synchronizing circuit once for each vibration of the arm 11 of the master pole changer V. Since the rates'of vibration of the other pole changers are approximate multiples of that of the pole changer V, it follows that each of them will vibrate its arm 1) a certain number of times for each single vibration of the master pole changerarm. In the case of the pole changer V which has a frequency of 33, the winding m will receive a pulsation of current through the branch 30 once in every two vibrations of its arm '0. In the case of the pole changer V these sychronizing impulses will be received once in three vibrations of its arms; and in the case of the pole changer V the synchronizing impulse will be received once in four vibrations of its arm. The effect of these synchronizing impulses is to keep the rates of vibration approximately constant, taking the low speed vibrator as a standard. If one of the arms has a tendency to slow down a little, it will obviously be pulled up each time the spirit of my invention, the nice synchronizing impulse comes, while on has a temlcncy to speed up will be down.

Fig. 2 is a skeleton diagram of amotlh tied layout for a separate mas er vib ato'r or sym-hronizer. In this figure the pole changers aml their non-essential elements are omittcil. the vibrators c; and the motor magnets hi being shown fitllietl by themselves. llach motor magnet has its initial or imli Vltltll motor winding *m, as before; and. each also has a syncln'onizing Winding m the circuit hei substailt ially the same as altflll) traced with the ililfereuceihat all lour pole changers are here shown with double windings. The synchronizing Wire 31. in this case passes to the contact 20 ot' an arm QM in a master vibrator set Vic, having a motor magnet him. This motor magnet like all the others tler'ir 's motive current. from the main battery. Wire 21, and is solidly attached to a. heavy frame or, which is groumleil. it will be observed that. the ribrator 0.1: ha.- no pole changing arms or contacts aml its mechanism throughout is exceedingly simple. This simplicity enables me to construct the device with great precision so as to maize it very accu ate in its operation. The arm, supporting spring, and arnuuurc. are all made in one piece and the device is suitably proportioned throughout so as to he accu *ately tuned to the master frequency for s m'chronizing purposes. I

Thus it will be seen that l have provided a means for causing synchronous operation of a plurality of pole changers and that such pole changers may be consideretl to constitule a plurality of current producing means each adapted to supply current of (lelinite characteristics to operate signaling apparatus designed to respond theeto.

i am aware that the system and. apparatus l have thus described may yarietl in many matters of detail Withoutdeparting from the living charnroducnon actoristic eature of Whichi th L of synchronizing impulses the vibri I tcrvals. My claims. therein-e are to be given a broad reading.

Having thus described my invention,

5 v hich are fed. to-

'\\'llfili I claim aml desire to secure by Lett s Patent is:

- 1. in an electrical signaling s -Jsteni. mechanism for producing a periodic I sling c u'rent otiilelinite frcipiency, a secoz rechanism for producing; a second periochc si naling current of ilelinile frequency and means whereby the pulsations of urin cnrrentproduced by uch secoml mechains: tend to maintain constant the treauci the signaling current produced by is! nu=chanism.

l in an electrical signaling system means m'mlucing a. periodic s 'naling current,

mug mechanisms at recurring in-' a' separate synchrenize' therefor, a common source of electric energy and means whereby the operation of such synchronizer tends to maintain constant the frequency of such signaling current.

' 3. in an clectri *al signaling system, a plurality of means for producing periodic Sig; naling currents, a con'nnon synchronizing (lerice or speed regulator therefor and means whereby the operation of such svnclnronizcr temls to maintain constant the frequency of such signaling currents.

el. luau electrical. system. a plurality of means for producing pcrioilic currents of tllll tl'tllll'. trcqncmries, a common synchronizing levi for such current reducing means and means whereby the v; oration of such synchronizer tends to maintain constant the frmpiency of such signaling currents.

In an electrical signaling system, a plurality of me us for producing periodic signaling currents, each of such means including a motor nechanism and a separate synchronizim mechanism, a common synchronize' and means whereby the ope ation of such common synchronizcr operates all of such synchroniZingmechanisms and tends to maintain constant. the frequency of such signalingcurrents.

(i. in an electrical signaling s stem, a plura ity all means for producing slgualingcun rents, each of such means having an imliviclual motor magnet and an auxilia y syn chroni'lcing magnet each of such motor magnets tending by its operation to cause an approximately constunt rate of movement, a common synchronizer and means whereby the operation of such sym-hronizcr tentls to maintain constant the rate of movement of each of such signal current producing means.

7. ln an electrical system. a plu 'ality of means tor producing sigualii currents 1 adapted to be operated at approximately constant speeds, a regulating magnet. for each of such current producing means a common mechanism for producing synchronizing current aml means whereby such sym-hronizing current actuates such regulating magnets and. thereby temls to maintain constant the speeds of such current producing means.

b. in an electrical system. a plinalil'y of current producing means individually tlriren at normally constant but alill'erent speeds, a. connnon symflnonizine device therefor and means for communicating synchronizing impulses jl rom such synclnxmizing device to such current producing; means, the rate of such impulses aml the rates oi" speed such ci rrcnt producing means being multiplies of one another.

l). in an electrical system. a plurality of currentproducing means iiuliviclually (lllVGD. at normally :onstant but (lillcrcnt spectls, a common synchronizing device therefor anti means for communicating synchronizing impulses from such synchronizing device to such current producing means.

30. In an electrical system, a plurality of "current producing means actuated by periodic current at approximately constant but different speeds, a common synchronizing device therefor, means for communicating synchronizing impulses from such synchronizing device tosuch current producing means at pro-determined intervals, the rates of speed of such current producing means being multiples of the rate of such synchronizing intervals.

11L In an electrical system, a current producing means adapted to be operated by periodic current, a synchronizing device and means for communicating synchronizing impulses of a frequency lower than the normal frequency of such current producing means from such synchronizing device to such current producing means whereby the frequency of such current producing means is maintained practically normal.

12. Inn an electrical signaling system, a

pole changer, an individual motor magnet therefor, a synchronizing magnet, and means to supply the latter with current impulses at recurring intervals, substantially as described.

13. lnan electrical signaling system, a

plurality of pole changers having individualmotor magnets and auxiliary synchronizing magnets," together with a common synchronizer connectedto said auxiliary magnets, substantially as described. 14. In an electrical signaling system, a plurality of pole changers tuned to Work at distinctive frequencies, and a common synchronizer supplying current thereto for synchronizing purposes at a frequency not exceeding that of the slowest of the pole changers, substantially as described.

15. In an electrical signaling system, a

plurality of Working pole changers for supplying signaling current at' diverse frequencies, and a regulator or synchronizer' commonto all of said pole'changers, the arrangement being such that the normal periods of the pole changers are approximately even multiples of the synchronizer period, substantially as described.

16. In an, electrical signaling system, a

plurality of pole changers Working at difierent frequencies, a motor ,n1agnet for each pole changer and circuit controlling means for said magnet periodically operated by its own pole changer, an auxiliary magnet for each pole changer, and a common vibrator supplying periodic synchronizing impulses to said auxiliary magnets, substantially as described. a

17. In an electrical signaling system, a plurality of pole changers operating at different frequencies, a tuned 'ibrating arm for each pole changer, a motor magnet for each arm having its circuit gbv'rned thereby, an auxiliary motor magnet for each arm, a common circuit for all of said auxilia y magnets, and a master vibrator adjuste to have a constant rate of vibration, adapted to supply current impulses to the circuit of the auxiliary magn ts at recurring intervals for regulating purposes, substantially as described.

18. In a telephone exchange system, an op erators cord circuit and selective ringing r key, in combination with a plurality of pole changers connected to said key, an'individcurrent producing mechanisms for producing current at suitable frequencies to actuate the ringers at the sub-stations, together with synchronizing means common to said harmonic mechanisms,

.20. In a telephone exchangesystem, an operators harmonic signaling apparatus comprising *a plurality of individually driven harmonic current producing means, together With a common synchronizer operated at constant speed.

In testimony whereof reliant M. snononf Witnesses:

WM. l/V. DEAN,

RAY H.- MANSON.

I atlix my signature. n presence of two Witnesses. 

